Paper bag feeder

ABSTRACT

AN ACCUMULATING CONVEYER AND SINGLE FEEDER FOR FOLDED SHEETS, ESPECIALLY OF MULTIPLE PLY SUCH AS BAG TUBES, IS PROVIDED. A STACK OF BAG TUBES IS PRESENTED VERTICALLY UPWARD UPON HORIZONTAL LOADING ARMS. SINGLE BAG TUBES ARE REMOVED FROM THE TOP OF THE PRESENTED STACK BY TRANSFER ARMS HAVING VACUUM CUPS. HOLD-BACK ELEMENTS CONSOLIDATE EACH BAG TUBE BY A DRAPING BEND. THIS LOCKS THE PLYS TOGETHER PREVENTING FAN-OUT FOR TROUBLE-FREE TRANSFER INTO A DOUBLE BELT CONVEYOR FOR A SUBSEQUENT OPERATION.

Sept. 20, 1971 C BRQWN, JR" ET AL 3,606,305.;

PAPER BAG FEEDER Filed Jan. 22, 1969 '7 Sheets-Sheet 1 4 Mlll v I mvsmofis 2 CHARLES K. BROWN JR. FIG. 1 DAVID KEBROWN ATTORNEY Sept. 20, 1971 w JR" ET AL 3,606,306

PAPER BAG FEEDER Filecl Jan. 22, 1969 7 Sheets-Sheet :I

SOONER INVENTORS CHARLES K. BROWN JR. [:7 2 DAVID K. BROWN ATTORNEY Sept. 20, 1971 WN, JR ETAL 3,606,306

PAPER BAG FEEDER Filed Jan. 22, 1969 7 Sheets-Sheet 3 SWITCH as ON CONVEYOR SOONER J (@J ELECT Ric CONTROL PANEL TO SOLINOID 83 nJvENmRs CHARLES K. BROWN JR. Fl 6. 3 DAVID K. BROWN ATTORNEY C. K. BROWN, JR., E-TAL Sept. 20, 1971 PAPER BAG FEEDER 7 Sheets-Sheet 4 Filed Jan. 22. 1969 F H 3 3 Illll] 6 a w w .w 4 0 I T 4 0 m 6 2 W m 0 0 M l K MM/ F 44, H w n 9 3 ..h 4 M fi W V H m II II a m uw 9 "3 M m w a w M 7/ "U a? 0; m Row 9 3 /0 W 4 7 w 4 v N 6 q 9 2 3 12 w 2\ 4, 1 II W n w, WW v H 7 H" II -i. M

FIG. 5

INVENTORS CHARLES K. BROWN JR DAVID K. BROWN ATTORNEY Sept. 20, 1971 c. K. BROWN, JR., EI'AL 3,606,306

PAPER BAG FEEDER '7 Sheets-Sheet 5 Filed Jan. 22; 1969 POWER SUPPLY TO SWITCH ON CONVEYOR FIG. 8

mvmons CHARLES K. BROWN JR DAVID-K. BROWN WAITING 4 POSITION PUMP ATTORNEY Sept. 20, 1971 ROW JR" ETAL 3,606,306

PAPER BAG FEEDER Filed Jan. 22, 1969 '7 Sheets-Sheet 6 a A s s I03 7/- FIG. .9 i

INVENT( )RS ATTORNEY Sept. 20, '1971 c, W JR" ET AL 3,606,306

PAPER BAG FEEDER Filed Jan. 22, 1969 7 Sheets-Sheet 7 /00 30A 1] c '9 f; I 22 i 22A 22 I00 [0/ B- A e s j 1/- /03 N 30 H6213 I /03 I luv l 5 FIG. 14 3b W H .Y |uTHgmmUu V v JD pi Z2 7-, III' l I00 MMWWWMM INVENTORS CHARLES K. BROWN JR.

DAVID K. BROWN BY waw(,%d%/

ATTORNEY United States Patent 3,606,306 PAPER BAG FEEDER Charles K. Brown, Jim, and David K. Brown, Richmond, Va., assignors to Brown-Fielder, Inc., Richmond, Va. Filed Jan. 22, 1969, er. No. 793,133 Int. Cl. B6511 1/18 US. Cl. 271-31 .8 Claims ABSTRACT OF THE DISCLOSURE An accumulating conveyer and single feeder for folded sheets, especially of multiple ply such as bag tubes, is provided. A stack of bag tubesis presented vertically upward upon horizontal loading arms. Single bag tubes are removed from the top of the presented stack by transfer arms having vacuum cups. Hold-back elements consolidate each bag tube by a draping bend. This locks the plys together preventing fan-out for trouble-free transfer into a double belt conveyer for a subsequent operation.

This invention relates generally to apparatus for manufacture of paper containers, and more particularly it pertains to a system for loading sewing machines with tubular stock.

I High capacity paper bags are usually closed at the bottom by a stitched seam. This operation is performed on sections of tubing which have been made beforehand on another machine. Such sections of bag stock when flattened may have as many as six layers or plys and also may be as long as five feet. Usually there is a bellows-like fold in the sides and one in the bottom which is known as a. gusset and which tends to open or fan-out.

A hopper for supplying the sections of tubing by bottom feed is not practical because of this large variable thickness. With top feeding at high speeds, the machine must be stopped to reload the hopper.

It is an object of this invention, therefore, to provide a machine for feeding bag stock from the top of a stack which is replenished from below by an automatically controlled carrier and thus can run continuously at high speed.

Another object of this invention is to provide a rapid transfer arrangement for single units of multiple wall bag stock which uses a vacuum pickup and unique break' away elements which preclude effectively the transfer of more than one bag per feed stroke.

Yet another object of this invention is to provide .apparatus and a novelmethod for vacuum cup handling of multiple-folded tubular stock to prevent the opening thereof while so supported.

Other objects and attendant advantages of this invention will become more readily apparent and understood from the following detailed specification and accompanying drawings in which:

FIG. 1 is a front elevation of a bag feeder machine incorporating features of this vinvention;

FIG. 2 is a vertical section taken on line 2-2 of FIG. 1;

FIG. 3 is a left side elevation of the bag feeder machine of FIG. 1;

FIG. 4 is a top view of the bag feeder machine of FIG. 1;

FIG. 5 is a view, of they upper right side of the bag feeder machine of FIG. 1;

' FIG. 6 is a view similar to'FIG. 5 but broken away to show details of an elevator conveyer drive arrangement;

FIG. 7 is a breakaway view, in perspective, illustrating details of the rocker arm drive;

FIG. 8 is a somewhat schematic depiction of the action of the suction cup carrier;

FIG. 9 is a front view illustrating the pick-up action of the vacuum transfer and the distortion of the top bag by the hold-down elements;

' FIG. 10 is a side view of the vacuum transfer arrangement of FIG. '9 with the action at the point of release to the delivery belts;

FIG. 11 is a detail perspective view of one of the side picker bars;

FIG. 12 is an enlarged perspective detail view showing the folding arrangement for arms of the elevator;

vFIG. 13 is a View similar to FIG. 9 but illustrating an adaptation of the vacuum pickup for extra long or flimsy bags;

FIG. 14 is plan view of one corner of the pickup area;

FIG. 15 is a side view of the elevator arm; and

FIGS. 16 and 17 illustrate successive steps in the closing of a gusset by the bag feeder machine of the present invention.

Essentially this bag feeder machine is a mechanism for accumulating a 2 to 5 minute supply of bags that can be fed one at a time onto a sewing machine. The accumulator and storage section is a chain drive mechanism.

Referring now to FIG. 1 of the drawing, reference numeral 1 indicates generally the frame, consisting of two vertical side plates and a base plate tied together by several transverse cross tie bars 2. These bars 2 are used also as component support members inside the machine. An elevator conveyor frame and chain guide 3 is provided that supports a series of arms 5 hingedly mounted on endless roller chains 29. These arms 5, in plurality, project outwardly in front in a shelf-like horizontally spaced relationship as shown best in FIG. 2 so that the operator of the bag feeder machine merely is required to. stack bags 30 on these arms 5 as they come up in sequence.

The arms 5 are driven upwardly by an electric motor drive 23. As the bags 30 move upwardly to the normal working level, they are automatically removed one at a time by a suction cup mechanism indicated by reference numerals 9 and 10. The suction cups 22 raise, then move the bags 30 rearwardly into the nip of a double delivery belt 54, 55 that carries the bags 30 outwardly and downwardly and deposits them on a sewing machine table (not shown).

At the bottom of each frame and chain guide 3, there are provided curved chutes 4 that deflect the elevator arms 5 around the bottom of the chain and pre -align them so that they will be in position to be lifted up in a horizontal position as the chains 29 travel upwardly. As soon as they have reached this horizontal position, they are then in a situation for loading, despite the continual,

ation of the bag thickness, differences in construction,

flexibility, all of which required much intricate mechanism which was not reliable under continued operation.

The present bag feeder machine by taking the bag 30- off the top of the stack and feeding into the pick-up area from beneath, makes it possible to continuously operate,

the machine and to load it simultaneously.

,Referring' now to FIG. 12, there is shown in'detaill a hinged connection of an arm 5 to chain 29 andthe support of the chain between the bottom guide track 3 B and the top guide track 3A. As depicted by the phantom lines, the arms 5 deflect quickly out of the way to 5a when the last bag 30 has been removed from that particular set of Patented Sept. 20, 1971 arms and they begin to pass over the upper bend of chain 29.

The next or exposed layer of bags 30 on the following set of arms 5 position for immediate pickup without interference at a feed rate as high as 120 or 130 bags per minute. Less than one-half a second is available to get the arms 5 out of the way and expose the next stack of bags 30 for the pickup action of the suction cups 22.

As shown in FIG. 2, the suction cups 22 are each supported with a coiled spring 46 on a sliding stem 21 to stem carrier 44. These carriers 44, are each, in turn, supported by a suction cup carrier frame A plurality of suction cup carrier frames 10 are attached to a common suction cup carrier main frame 9 which transversely is supported in the machine on hanger links 42, one on each side of the machine. The links 42. depend from a fixed pivot 43.

The rear of the carrier frame 9 is supported on spaced rocker arms 19 and attached to an oscillating shaft 18. The rocker arm 20 is a double arm or bell crank type. The second connection on this rocker arm or bell crank 20 is in turn actuated by a crank 41 which is mounted on the output shaft of an indexing or one revolution clutch 80 as further shown in FIG. 3.

The one revolution clutch -80 is released by a triplatch 81 which through a link 82 is operated by a solenoid 83. The clutch 80 is driven continuously by a chain '84 on sprocket 85 from a drive unit 86. Power leads 87 for solenoid 83 are routed to a control switch 88 shown in FIGS. 2 and 3.

The switch 88 is in the path of a conveyor 90 of a sewing machine positioned 01f of the drawing to the right. A mount 89 for switch 88 is made adjustable as shown by the arrows in FIG. 2 so that a signal to discharge a bag onto the sewing machine from the top feeder arrangement can be advanced or retarded to synchronize properly. Suitably spaced timing lugs, on this conveyor 90 trip the switch 88 at desired bag intervals and also move the bags 30.

'On the left in FIG. 1 and in a side view in FIG. 5, there is shown a cam 17 at the side of the machine. This cam 17 is so positioned on the rocker arm shaft '18 to operate a common control valve 14 for the suction cups 22 to apply vacuum at pickup times and break vacuum at release times. Thus, a bag 30 will be picked up and released quickly and easily to the double belts 54, to take over and move the bag 30 down to the conveyor 90 of the sewing table. This simple mechanism gives very little trouble because the timing is taken directly from the shaft 18 that is providing the motion for lifting the cups 22.

Now with reference to FIGS. 1 and 2, a flexible hose is attached at one end to tubular slidable supports 44 of the cups 22. The other end communicates with the hollow frames 10 that support the suction cups 22. Another hose 11 leads from the other end of frame 10 to a valve 13 that is junctured with a main vacuum manifold line as best shown in FIG. 4.

The manifold line 12 is interrupted by the cam driven control valve 14 on its way down to the vacuum pump 15 driven by the motor 16. -For shorter bags 30, all the cups 22 are not required. Accordingly, certain ones may be cut off by their valves 13.

The cooperation of valve 14 and the suction cup carrier pickup and waiting or feed position is illustrated in FIG. 8. It is important to this method of dip receiving and extending of the bags 30 to have them at the proper working level so that the suction cups 22 can pick them up with limited lifting and, when picked up, that the bags 30 not be so high initially as to prevent the proper breakaway of the bag :30 being fed from the stack of bags 30' underneath.

A proper working level is controlled by a probe switch 47 mounted on a support 48 which permits adjustment vertically for setting the desired level, As the bags 30 are fed off depleting the stack, the switch 48 closes and energizes a clutch 23a in the elevator drive system of which reference 23 is the motor reducer portion. This drive system 23 rotates a square shaft 27. Shaft 27 on journals 26 is transversely positioned through the bag feeder machine so that it engages all of the elevator track chain sprockets 28 and coordinates and drives the movement of the elevator arms 5 upwardly to carry the bags 30 to the working level.

At the working level, the vacuum oups 22 pick up the bags 30 one at a time as they move with the frame 10 and the main frame 9. The delivery belts 54 and 55 are tensioned and supported at the top on hanger frames 51 which journal idler pulleys 52 and 53.

Coiled springs 58 extend from a hanger 49 on a frame cross bar 2 to the journalling hanger 51 to provide the bias. This pair of belts. 54 and 55 grip the bag 30 between them so to provide a controlled delivery of the bags 30 to the sewing table.

These belts 54, 55 are driven by lower pulleys 58 on counter-rotating shafts 56 and 57. The shafts 56' and 57 are rotated by a chain 60, shown in FIG. 3, and a pair of sprockets 59. Motor reducer 61 provides the motive power for these belts and runs continuously at all times.

The pickup mechanism or carrier frame 9 is driven from the motor reducer 86 driving the single revolution clutch through the chain 84 as previously mentioned in connection with FIG. 7. The input to the single revolution clutch 80 runs continuously, and is released at timed intervals by switch 88 associated with the sewing machine conveyer 90'.

Each time the switch 88 is closed, it sends a signal through the line 87 to the solenoid 8 3 which releases latch 81 through the connection with link 82. The release of this latch 81 permits the clutch 80' to make one revolution and stop. The drive is thus discontinued so that the carrier frame for the suction cups 22 does not cycle again until the next signal.

This single revolution clutch 80 is driven at a speed in excess of the maximum rate of speed desired. Therefore, there always will be a slight dwell between bag feeding intervals of bags 30 to the sewing table, to automatically keep the feeder in time with the sewing machine, a very important point.

As was mentioned earlier, the machine is capable of running to speed in excess of a minute, which means that this latch 81 releases and re-engages the clutch 80 every half second or less.

FIG. 6 shows the elevator drive mechanism including the drive motor 23 which runs continuously. The motion is controlled through the clutch 23a which is of electro-magnetic type coupled between the motor 23 and the speed reducer 23b. When the clutch 23a is energized by closure of probe switch 47, due to the lowering of the level of bags 30 being taken off of arms 5, the switch 47 will make contact, energize the clutch 23a and thus provide an output impulse from the motor reducer 23b through the chain 25 and a sprocket connection to turn the square shaft 27.

In FIGS. 2 and 6, it will be noted that this ele vator drive square shaft 27 engages sprockets 28 which drive the endless elevator chains 29 carrying arms 5 around and upwardly to bring bags 30 into contact with the probe svw'tch 47. The switch 47 on opening the circuit and de-energizing the clutch 23a stops the upward movement of the bags.

When the last bag 30 goes olf any given set of arms 5, there is immediate closure of switch 47 and the clutch 23a energizes and continues to drive for the time necessary to swing the empty arms 5 over and drop out of the way so that the next bag 30 can be picked up from the following stack of bags 30.

The next stack of bags 30 then arrives at the working level, which is defined by the contact point of the probe switch 47, and the cycle repeats.

The bag pickup and separation operation will now be described. In FIG. 9, a stack of bags 30' is shown being picked up by three suction cups 22. It will be noted that the top bag is being held down at each end by pickup bars 100. These pickup bars 100 hold back the bags 30 in the stack and permit only the first bag or top bag to be raised up above the surface of the second bag allowing air to vent between the bags 30 and preventing the dragging out of more than one bag at a time due to the suction between the layers of paper which make up the bags.

A further reason for lifting and holding back the bag 30 in this fashion is to drag the ends downwardly to closeup or lock the gusset. -A gusset is a double fold or triple fold in the edge of the bag.

Referring now to FIG. 16, top and bottom flaps 30a and 30b of the gusset are shown with 30c representing the middle fold. If the bag 30 was picked up without this hold back at its extremes, the gusset would not close as shown in FIG. 17 but would fall open as shown by phantom lines in FIG. 10 and the bag 30 would not enter the nip of belts 54, 55 properly. Possibly the bags 30 would be creased backwards and if it did get on the sewing table without jamming, it would be improperly sewed and become an unmarketable product.

FIGS. 11 and 14 depict details of construction of the picker bar 100. The bar 100 is on a swinging mount 101, with an adjusting screw 102 positioned so that it can be set to release the bags 30 at a common level with limit switch 47 as set to control the pick-off level of the bags 30.

In a preferred lifting arrangement shown in FIG. 13, it will be noted that the contour of the lifted bar 30a is in the shape of an inverted W rather than the depending side fiat contour shown in FIG. 9. The purpose of this modified lift pattern is to hold down the middle of the second bag 30 or the bag 30 on the stack by extending the center vacuum cup 22a downwardly so it does not follow the first.

On very flimsy or long bags 30, the friction between the bags 30 under the pickup bars 100 tends to make the second bag follow the first bag due to the inward draw 01 the bag ends as it is being lifted free of the pickup bars. By maintaining a depression as shown in the middle of the bag 30, the stack is stabilized against extra or multiple feed of the bags.

Weights 103 hung on the pickup bars 100 provide a bias pressure on the ends of the bag 30 depending on the weight of the bag being fed. Hea-vy bags 30 will require more weight than flimsy bags which require practically none. A bag location stop 104 is mounted in this area to align the bags 30 on one side. As shown in FIG. 1, adjustably spaced plate guides 6 and 7 are provided to align the bags end wise.

Referring to FIGS. 1 and 2, a bar 70 is hung on two cables 71 on the right and left sides of the bag feeder machine which pass over a pair of pulleys 72 supported by pulley brackets 73. The cables then drop down on the left hand side of the machine and hook onto a counterweight 74.

FIG. 2 shows how the counterweight tends to raise the bar 70. The purpose is to open up the space between arm at the point where loading thereof is taking place. This speeds up a loading operation considerably.

When each particularly level is loaded, the operator simply pulls down the bar 70 and hooks it under the set of arms 5 just loaded. This causes the arms 5 to be raised up exposing the empty set of arms 5 underneath for loading in the next sequence.

"In practice, the loading operations are done in a plant where several machines are lined up. It was found that it is very practical for one man to feed four sewing machines with the bag feeder machine here disclosed.

Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A paper bag feeder comprising: means for serially feeding by suction cup engagement sheets of folded bag stock from the top of a stack of said sheets, means for restraining a folded portion of each sheet on removal thereof from the stack of sheets including a bar positioned to engage each said sheet in succession adjacent an edge thereof opposite said suction cup engagement, gravity means for urging said bar against the engaged sheet, means for continually replenishing the folded sheets from below the stack of sheets, and means for synchronizing the said serial feedings and replenishment means.

2. A paper bag feeder as recited in claim 1, the said serial feeding means comprising a motor driven pivoted mechanism having at least two suction cups positioned to engage successively each said sheet of a stack of sheets intermediate the edges thereof for pickup and movement of the sheet on pivoting of the said mechanism, and rotary means for receiving the sheets moved thereby.

3. A paper bag feeder as recited in claim 1, the said means for continually replenishing the folded sheets from below comprising elevator means including a vertically rotatable endless member, a motor adapted to rotate the endless member, and a plurality of shelf arms hingedly connected to the endless member in respective spaced relation and thereby adapted to receive plural stacks of folded bag stock.

4. A paper bag feeder as recited in claim 3, the said plurality of shelf arms having projection supports at the respective hinged connections, the projection supports being operative on the ascending side of the said vertical rotation.

5. A paper bag feeder as recited in claim 2, the said means for synchronizing the serial feeding means comprising a switch adapted to control the said drive of the pivoted mechanism, a lug on the said rotary means adapted to operate the switch on rotation of the rotary means, and a valve actuated by the rotary means for controlling the vacuumof said suction cup.

6. A paper bag feeder as recited in claim 2, the said serial feeding means having plural suction cups thereon, a said cup positioned centrally of the feeding means and lower than another said cup, whereby the said mechanism is adapted to depress a center area of a sheet of folded bag stock on pickup by the mechanism to facilitate separation of the sheet picked up from the next in succession.

7. A paper bag feeder as recited in claim 3, and an arm raising bar having takeup means adapted for lateral engagement with a plurality of the shelf arms, thereby increasing clearance beneath the engaged shelf arms for loading bag stock onto the elevator means.

8. A paper bag feeder as recited in claim 5, the said drive of the pivoted mechanism including a solenoid released single revolution clutch actuated by the said control switch on operation of the rotary means.

References Cited UNITED STATES PATENTS 1,110,704 9/1914 Minnick 271-20 1,277,139 8/1918 Schroeder et al. 27162(A) 2,108,702 2/ 1938 Backhouse 27126UX 2,846,220 8/1958 Mestre 271--31 3,269,725 8/1966 Schwebel 271--62(A) 3,410,550 11/1968 Weidman et al. 27131X JOSEPH WEGBREIT, Primary Examiner US Cl. X.R. 27l-62A 

